From 61d0326a5b1c11a8f2e8e31ec9093e81daa26588 Mon Sep 17 00:00:00 2001

From: David Herrmann <dh.herrmann@gmail.com>

Date: Thu, 2 Oct 2014 19:47:21 +0200

Subject: [PATCH] terminal/unifont: add built-in fallback glyph

In case we cannot render a glyph, we want a fallback we can display

instead. If we rely on the font itself to provide the fallback character,

we have nothing to display if that character is not available. Therefore,

add a static fallback that we can use at any time.

---

 src/libsystemd-terminal/unifont.c | 18 ++++++++++++++++++

 src/libsystemd-terminal/unifont.h |  1 +

 2 files changed, 19 insertions(+)

diff --git a/src/libsystemd-terminal/unifont.c b/src/libsystemd-terminal/unifont.c

index 7520015988..2acfa9821a 100644

--- a/src/libsystemd-terminal/unifont.c

+++ b/src/libsystemd-terminal/unifont.c

@@ -221,3 +221,21 @@ int unifont_lookup(unifont *u, unifont_glyph *out, uint32_t ucs4) {

                 memcpy(out, &g, sizeof(g));

         return 0;

 }

+

+void unifont_fallback(unifont_glyph *out) {

+        static const uint8_t fallback_data[] = {

+                /* unifont 0xfffd '�' (unicode replacement character) */

+                0x00, 0x00, 0x00, 0x7e,

+                0x66, 0x5a, 0x5a, 0x7a,

+                0x76, 0x76, 0x7e, 0x76,

+                0x76, 0x7e, 0x00, 0x00,

+        };

+

+        assert(out);

+

+        out->width = 8;

+        out->height = 16;

+        out->stride = 1;

+        out->cwidth = 1;

+        out->data = fallback_data;

+}

diff --git a/src/libsystemd-terminal/unifont.h b/src/libsystemd-terminal/unifont.h

index 0ded61472f..30527cb3fa 100644

--- a/src/libsystemd-terminal/unifont.h

+++ b/src/libsystemd-terminal/unifont.h

@@ -54,3 +54,4 @@ unsigned int unifont_get_width(unifont *u);

 unsigned int unifont_get_height(unifont *u);

 unsigned int unifont_get_stride(unifont *u);

 int unifont_lookup(unifont *u, unifont_glyph *out, uint32_t ucs4);

+void unifont_fallback(unifont_glyph *out);